
/*
** Some generic functions over Lua objects
** See Copyright Notice in lua.h
*/

#include <ctype.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>

#define lobject_c

#include "lua.h"

#include "ldo.h"
#include "lmem.h"
#include "lobject.h"
#include "lstate.h"
#include "lstring.h"
#include "lvm.h"

/* function to convert a string to a lua_Number */
#ifndef lua_str2number
#define lua_str2number(s,p)     strtod((s), (p))
#endif

const TObject luaO_nilobject = { LUA_TNIL, {NULL} };

/*
** converts an integer to a "floating point byte", represented as
** (mmmmmxxx), where the real value is (xxx) * 2^(mmmmm)
*/
int
luaO_int2fb(unsigned int x)
{
  int m = 0;                           /* mantissa */
  while (x >= (1 << 3)) {
    x = (x + 1) >> 1;
    m++;
  }
  return (m << 3) | cast(int, x);
}

/* *INDENT-OFF* */
int
luaO_log2(unsigned int x)
{
  static const lu_byte log_8[255] = {
    0,
    1,1,
    2,2,2,2,
    3,3,3,3,3,3,3,3,
    4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
    5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
    6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
    6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
    7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7
  };
  if (x >= 0x00010000) {
    if (x >= 0x01000000)
      return log_8[((x >> 24) & 0xff) - 1] + 24;
    else
      return log_8[((x >> 16) & 0xff) - 1] + 16;
  } else {
    if (x >= 0x00000100)
      return log_8[((x >> 8) & 0xff) - 1] + 8;
    else if (x)
      return log_8[(x & 0xff) - 1];
    return -1;                  /* special `log' for 0 */
  }
}
/* *INDENT-ON* */

int
luaO_rawequalObj(const TObject * t1, const TObject * t2)
{
  if (ttype(t1) != ttype(t2))
    return 0;
  else
    switch (ttype(t1)) {
    case LUA_TNIL:
      return 1;
    case LUA_TNUMBER:
      return nvalue(t1) == nvalue(t2);
    case LUA_TBOOLEAN:
      return bvalue(t1) == bvalue(t2);  /* boolean true must be 1 !! */
    case LUA_TLIGHTUSERDATA:
      return pvalue(t1) == pvalue(t2);
    default:
      lua_assert(iscollectable(t1));
      return gcvalue(t1) == gcvalue(t2);
    }
}

int
luaO_str2d(const char *s, lua_Number * result)
{
  char *endptr;
  lua_Number res = lua_str2number(s, &endptr);
  if (endptr == s)
    return 0;                   /* no conversion */
  while (isspace((unsigned char)(*endptr)))
    endptr++;
  if (*endptr != '\0')
    return 0;                   /* invalid trailing characters? */
  *result = res;
  return 1;
}

static void
pushstr(lua_State * L, const char *str)
{
  setsvalue2s(L->top, luaS_new(L, str));
  incr_top(L);
}

/* this function handles only `%d', `%c', %f, and `%s' formats */
const char *
luaO_pushvfstring(lua_State * L, const char *fmt, va_list argp)
{
  int n = 1;
  pushstr(L, "");
  for (;;) {
    const char *e = strchr(fmt, '%');
    if (e == NULL)
      break;
    setsvalue2s(L->top, luaS_newlstr(L, fmt, e - fmt));
    incr_top(L);
    switch (*(e + 1)) {
    case 's':
      pushstr(L, va_arg(argp, char *));
      break;
    case 'c':
      {
        char buff[2];
        buff[0] = cast(char, va_arg(argp, int));
        buff[1] = '\0';
        pushstr(L, buff);
        break;
      }
    case 'd':
      setnvalue(L->top, cast(lua_Number, va_arg(argp, int)));
      incr_top(L);
      break;
    case 'f':
      setnvalue(L->top, cast(lua_Number, va_arg(argp, l_uacNumber)));
      incr_top(L);
      break;
    case '%':
      pushstr(L, "%");
      break;
    default:
      lua_assert(0);
    }
    n += 2;
    fmt = e + 2;
  }
  pushstr(L, fmt);
  luaV_concat(L, n + 1, L->top - L->base - 1);
  L->top -= n;
  return svalue(L->top - 1);
}

const char *
luaO_pushfstring(lua_State * L, const char *fmt, ...)
{
  const char *msg;
  va_list argp;
  va_start(argp, fmt);
  msg = luaO_pushvfstring(L, fmt, argp);
  va_end(argp);
  return msg;
}

void
luaO_chunkid(char *out, const char *source, int bufflen)
{
  if (*source == '=') {
    strncpy(out, source + 1, bufflen);  /* remove first char */
    out[bufflen - 1] = '\0';    /* ensures null termination */
  } else {                      /* out = "source", or "...source" */
    if (*source == '@') {
      int l;
      source++;                 /* skip the `@' */
      bufflen -= sizeof(" `...' ");
      l = strlen(source);
      strcpy(out, "");
      if (l > bufflen) {
        source += (l - bufflen);        /* get last part of file name */
        strcat(out, "...");
      }
      strcat(out, source);
    } else {                    /* out = [string "string"] */
      int len = strcspn(source, "\n"); /* stop at first newline */
      bufflen -= sizeof(" [string \"...\"] ");
      if (len > bufflen)
        len = bufflen;
      strcpy(out, "[string \"");
      if (source[len] != '\0') {        /* must truncate? */
        strncat(out, source, len);
        strcat(out, "...");
      } else
        strcat(out, source);
      strcat(out, "\"]");
    }
  }
}

/*
 * Local Variables:
 * c-basic-offset: 2
 * indent-tabs-mode: nil
 * End:
 */
